RESUMO
Nutritional status potentially influences immune responses; however, how nutritional signals regulate cellular dynamics and functionality remains obscure. Herein, we report that temporary fasting drastically reduces the number of lymphocytes by â¼50% in Peyer's patches (PPs), the inductive site of the gut immune response. Subsequent refeeding seemingly restored the number of lymphocytes, but whose cellular composition was conspicuously altered. A large portion of germinal center and IgA+ B cells were lost via apoptosis during fasting. Meanwhile, naive B cells migrated from PPs to the bone marrow during fasting and then back to PPs during refeeding when stromal cells sensed nutritional signals and upregulated CXCL13 expression to recruit naive B cells. Furthermore, temporal fasting before oral immunization with ovalbumin abolished the induction of antigen-specific IgA, failed to induce oral tolerance, and eventually exacerbated food antigen-induced diarrhea. Thus, nutritional signals are critical in maintaining gut immune homeostasis.
Assuntos
Linfócitos B/fisiologia , Imunidade nas Mucosas , Animais , Antígenos/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Medula Óssea/imunologia , Medula Óssea/metabolismo , Quimiocina CXCL13/genética , Quimiocina CXCL13/metabolismo , Jejum , Regulação da Expressão Gênica , Glicólise , Imunoglobulina A/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estado Nutricional , Ovalbumina/imunologia , Nódulos Linfáticos Agregados/imunologia , Nódulos Linfáticos Agregados/metabolismo , Nódulos Linfáticos Agregados/patologia , Receptores CXCR5/genética , Receptores CXCR5/metabolismo , Transdução de Sinais , Células Estromais/citologia , Células Estromais/metabolismo , Serina-Treonina Quinases TOR/metabolismoRESUMO
Caloric restriction is known to improve inflammatory and autoimmune diseases. However, the mechanisms by which reduced caloric intake modulates inflammation are poorly understood. Here we show that short-term fasting reduced monocyte metabolic and inflammatory activity and drastically reduced the number of circulating monocytes. Regulation of peripheral monocyte numbers was dependent on dietary glucose and protein levels. Specifically, we found that activation of the low-energy sensor 5'-AMP-activated protein kinase (AMPK) in hepatocytes and suppression of systemic CCL2 production by peroxisome proliferator-activator receptor alpha (PPARα) reduced monocyte mobilization from the bone marrow. Importantly, we show that fasting improves chronic inflammatory diseases without compromising monocyte emergency mobilization during acute infectious inflammation and tissue repair. These results reveal that caloric intake and liver energy sensors dictate the blood and tissue immune tone and link dietary habits to inflammatory disease outcome.
Assuntos
Restrição Calórica , Monócitos/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Adulto , Animais , Antígenos Ly/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Quimiocina CCL2/deficiência , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Feminino , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/citologia , PPAR alfa/deficiência , PPAR alfa/genética , PPAR alfa/metabolismoRESUMO
Fasting is associated with improved outcomes in cancer. Here, we investigated the impact of fasting on natural killer (NK) cell anti-tumor immunity. Cyclic fasting improved immunity against solid and metastatic tumors in an NK cell-dependent manner. During fasting, NK cells underwent redistribution from peripheral tissues to the bone marrow (BM). In humans, fasting also reduced circulating NK cell numbers. NK cells in the spleen of fasted mice were metabolically rewired by elevated concentrations of fatty acids and glucocorticoids, augmenting fatty acid metabolism via increased expression of the enzyme CPT1A, and Cpt1a deletion impaired NK cell survival and function in this setting. In parallel, redistribution of NK cells to the BM during fasting required the trafficking mediators S1PR5 and CXCR4. These cells were primed by an increased pool of interleukin (IL)-12-expressing BM myeloid cells, which improved IFN-γ production. Our findings identify a link between dietary restriction and optimized innate immune responses, with the potential to enhance immunotherapy strategies.
Assuntos
Jejum , Células Matadoras Naturais , Camundongos Endogâmicos C57BL , Animais , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Camundongos , Humanos , Neoplasias/imunologia , Medula Óssea/imunologia , Medula Óssea/metabolismo , Camundongos Knockout , Interferon gama/metabolismo , Interferon gama/imunologia , Baço/imunologia , Baço/metabolismo , Imunidade Inata/imunologia , Interleucina-12/metabolismo , Interleucina-12/imunologia , Receptores CXCR4/metabolismoRESUMO
We have uncovered the existence of extracellular vesicle (EV)-mediated signaling between cell types within the adipose tissue (AT) proper. This phenomenon became evident in our attempts at generating an adipocyte-specific knockout of caveolin 1 (cav1) protein. Although we effectively ablated the CAV1 gene in adipocytes, cav1 protein remained abundant. With the use of newly generated mouse models, we show that neighboring endothelial cells (ECs) transfer cav1-containing EVs to adipocytes in vivo, which reciprocate by releasing EVs to ECs. AT-derived EVs contain proteins and lipids capable of modulating cellular signaling pathways. Furthermore, this mechanism facilitates transfer of plasma constituents from ECs to the adipocyte. The transfer event is physiologically regulated by fasting/refeeding and obesity, suggesting EVs participate in the tissue response to changes in the systemic nutrient state. This work offers new insights into the complex signaling mechanisms that exist among adipocytes, stromal vascular cells, and, potentially, distal organs.
Assuntos
Adipócitos/metabolismo , Células Endoteliais/metabolismo , Vesículas Extracelulares/metabolismo , Jejum/metabolismo , Transdução de Sinais , Animais , Caveolina 1/genética , Caveolina 1/metabolismo , Linhagem Celular , Células Cultivadas , Endotélio Vascular/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Diet profoundly influences physiology. Whereas over-nutrition elevates risk for disease via its influence on immunity and metabolism, caloric restriction and fasting appear to be salutogenic. Despite multiple correlations observed between diet and health, the underlying biology remains unclear. Here, we identified a fasting-induced switch in leukocyte migration that prolongs monocyte lifespan and alters susceptibility to disease in mice. We show that fasting during the active phase induced the rapid return of monocytes from the blood to the bone marrow. Monocyte re-entry was orchestrated by hypothalamic-pituitary-adrenal (HPA) axis-dependent release of corticosterone, which augmented the CXCR4 chemokine receptor. Although the marrow is a safe haven for monocytes during nutrient scarcity, re-feeding prompted mobilization culminating in monocytosis of chronologically older and transcriptionally distinct monocytes. These shifts altered response to infection. Our study shows that diet-in particular, a diet's temporal dynamic balance-modulates monocyte lifespan with consequences for adaptation to external stressors.
Assuntos
Medula Óssea , Monócitos , Camundongos , Animais , Células da Medula Óssea , Jejum , Quimiocinas/metabolismoRESUMO
The liver plays a pivotal role in metabolism and xenobiotic detoxification, processes that must be particularly efficient when animals are active and feed. A major question is how the liver adapts to these diurnal changes in physiology. Here, we show that, in mice, liver mass, hepatocyte size, and protein levels follow a daily rhythm, whose amplitude depends on both feeding-fasting and light-dark cycles. Correlative evidence suggests that the daily oscillation in global protein accumulation depends on a similar fluctuation in ribosome number. Whereas rRNA genes are transcribed at similar rates throughout the day, some newly synthesized rRNAs are polyadenylated and degraded in the nucleus in a robustly diurnal fashion with a phase opposite to that of ribosomal protein synthesis. Based on studies with cultured fibroblasts, we propose that rRNAs not packaged into complete ribosomal subunits are polyadenylated by the poly(A) polymerase PAPD5 and degraded by the nuclear exosome.
Assuntos
Fígado/citologia , Fígado/fisiologia , Ribossomos/metabolismo , Animais , Núcleo Celular/metabolismo , Tamanho Celular , Ritmo Circadiano , Exossomos/metabolismo , Hepatócitos/citologia , Hepatócitos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fotoperíodo , Processamento Pós-Transcricional do RNA , RNA Ribossômico/genética , Proteínas Ribossômicas/genética , Ribossomos/químicaRESUMO
Time-restricted eating (TRE) is a dietary intervention that limits food consumption to a specific time window each day. The effect of TRE on body weight and physiological functions has been extensively studied in rodent models, which have shown considerable therapeutic effects of TRE and important interactions among time of eating, circadian biology, and metabolic homeostasis. In contrast, it is difficult to make firm conclusions regarding the effect of TRE in people because of the heterogeneity in results, TRE regimens, and study populations. In this review, we 1) provide a background of the history of meal consumption in people and the normal physiology of eating and fasting; 2) discuss the interaction between circadian molecular metabolism and TRE; 3) integrate the results of preclinical and clinical studies that evaluated the effects of TRE on body weight and physiological functions; 4) summarize other time-related dietary interventions that have been studied in people; and 4) identify current gaps in knowledge and provide a framework for future research directions.
Assuntos
Ritmo Circadiano , Jejum , Peso Corporal , Ritmo Circadiano/fisiologia , Ingestão de Alimentos , Jejum/fisiologia , HumanosRESUMO
Stem cells maintain tissues by balancing self-renewal with differentiation. A stem cell's local microenvironment, or niche, informs stem cell behavior and receives inputs at multiple levels. Increasingly, it is becoming clear that the overall metabolic status of an organism or metabolites themselves can function as integral members of the niche to alter stem cell fate. Macroscopic dietary interventions such as caloric restriction, the ketogenic diet, and a high-fat diet systemically alter an organism's metabolic state in different ways. Intriguingly, however, they all converge on a propensity to enhance self-renewal. Here, we highlight our current knowledge on how dietary changes feed into stem cell behavior across a wide variety of tissues and illuminate possible explanations for why diverse interventions can result in similar stem cell phenotypes. In so doing, we hope to inspire new avenues of inquiry into the importance of metabolism in stem cell homeostasis and disease.
Assuntos
Dieta , Células-Tronco/fisiologia , Animais , Dieta Hiperlipídica/efeitos adversos , Jejum/fisiologia , Glucose/metabolismo , Humanos , Metabolismo dos Lipídeos/fisiologia , Células-Tronco/microbiologia , Células-Tronco/parasitologia , Estresse Fisiológico/fisiologiaRESUMO
Chronic caloric restriction (CR) has powerful anticarcinogenic actions in both preclinical and clinical studies but may be difficult to sustain. As an alternative to CR, there has been growing interest in intermittent fasting (IF) in both the scientific and lay community as a result of promising study results, mainly in experimental animal models. According to a survey by the International Food Information Council Foundation, IF has become the most popular diet in the last year, and patients with cancer are seeking advice from oncologists about its beneficial effects for cancer prevention and treatment. However, as discussed in this review, results from IF studies in rodents are controversial and suggest potential detrimental effects in certain oncologic conditions. The effects of IF on human cancer incidence and prognosis remain unknown because of a lack of high-quality randomized clinical trials. Preliminary studies suggest that prolonged fasting in some patients who have cancer is safe and potentially capable of decreasing chemotherapy-related toxicity and tumor growth. However, because additional trials are needed to elucidate the risks and benefits of fasting for patients with cancer, the authors would not currently recommend patients undergoing active cancer treatment partake in IF outside the context of a clinical trial. IF may be considered in adults seeking cancer-prevention benefits through means of weight management, but whether IF itself affects cancer-related metabolic and molecular pathways remains unanswered.
Assuntos
Jejum , Neoplasias/terapia , Animais , Restrição Calórica , Ensaios Clínicos como Assunto , Dieta , Humanos , Obesidade/complicações , Prognóstico , RiscoRESUMO
Vitamin A (retinol) is distributed via the blood bound to its specific carrier protein, retinol-binding protein 4 (RBP4). Retinol-loaded RBP4 is secreted into the circulation exclusively from hepatocytes, thereby mobilizing hepatic retinoid stores that represent the major vitamin A reserves in the body. The relevance of extrahepatic retinoid stores for circulating retinol and RBP4 levels that are usually kept within narrow physiological limits is unknown. Here, we show that fasting affects retinoid mobilization in a tissue-specific manner, and that hormone-sensitive lipase (HSL) in adipose tissue is required to maintain serum concentrations of retinol and RBP4 during fasting in mice. We found that extracellular retinol-free apo-RBP4 induces retinol release by adipocytes in an HSL-dependent manner. Consistently, global or adipocyte-specific HSL deficiency leads to an accumulation of retinoids in adipose tissue and a drop of serum retinol and RBP4 during fasting, which affects retinoid-responsive gene expression in eye and kidney and lowers renal retinoid content. These findings establish a novel crosstalk between liver and adipose tissue retinoid stores for the maintenance of systemic vitamin A homeostasis during fasting.
Assuntos
Adipócitos , Jejum , Proteínas Plasmáticas de Ligação ao Retinol , Esterol Esterase , Vitamina A , Proteínas Plasmáticas de Ligação ao Retinol/metabolismo , Proteínas Plasmáticas de Ligação ao Retinol/genética , Animais , Vitamina A/metabolismo , Vitamina A/sangue , Jejum/metabolismo , Camundongos , Adipócitos/metabolismo , Esterol Esterase/metabolismo , Esterol Esterase/genética , Fígado/metabolismo , Tecido Adiposo/metabolismo , Camundongos Knockout , Camundongos Endogâmicos C57BLRESUMO
Several observational studies have suggested that proton-pump inhibitor (PPI) use might increase diabetes risk, but the mechanism remains unclear. This study aimed to investigate the effects of PPI use on gut microbiota and bile acids (BAs) profiles, and to explore whether these changes could mediate the association of PPIs use with fasting blood glucose (FBG) levels and insulin resistance (IR) in Chinese population. A cross-sectional study was conducted in Shenzhen, China, from April to August 2021, enrolled 200 eligible patients from the local hospital. Participants completed a questionnaire and provided blood and stool samples. Gut microbiome was measured by16S rRNA gene sequencing, and bile acids were quantified by UPLC-MS/MS. Insulin resistance (IR) was assessed using the Homeostasis Model Assessment 2 (HOMA2-IR). PPI use was positively associated with higher levels of FBG and HOMA2-IR after controlling for possible confounders. PPI users exhibited a decreased Firmicutes and an increase in Bacteroidetes phylum, alongside higher levels of glycoursodeoxycholic acid (GUDCA) and taurochenodeoxycholic acid (TCDCA). Higher abundances of Bacteroidetes and Fusobacterium as well as higher levels of TCDCA in PPI users were positively associated with elevated FBG or HOMA2-IR. Mediation analyses indicated that the elevated levels of FBG and HOMA2-IR with PPI use were partially mediated by the alterations in gut microbiota and specific BAs (i.e., Fusobacterium genera and TCDCA). Long-term PPI use may increase FBG and HOMA2-IR levels, and alterations in gut microbiota and BAs profiles may partially explain this association.
Assuntos
Microbioma Gastrointestinal , Resistência à Insulina , Humanos , Inibidores da Bomba de Prótons/efeitos adversos , Ácidos e Sais Biliares , Cromatografia Líquida , Estudos Transversais , Espectrometria de Massas em Tandem , Bacteroidetes , Glucose/farmacologiaRESUMO
New neurones are generated throughout life in the mammalian brain in a process known as adult hippocampal neurogenesis (AHN). Since this phenomenon grants a high degree of neuroplasticity influencing learning and memory, identifying factors that regulate AHN may be important for ameliorating age-related cognitive decline. Calorie restriction (CR) has been shown to enhance AHN and improve memory, mediated by the stomach hormone, ghrelin. Intermittent fasting (IF), a dietary strategy offering more flexibility than conventional CR, has also been shown to promote aspects of AHN. The 5:2 diet is a popular form of IF; however, its effects on AHN are not well characterised. To address this, we quantified AHN in adolescent and adult wild-type and ghrelin-receptor-deficient mice following 6 weeks on a 5:2 diet. We report an age-related decline in neurogenic processes. However, the 5:2 diet does not increase AHN nor enhance memory performance, suggesting that this specific form of IF is ineffective in promoting brain plasticity to support learning.
Assuntos
Grelina , Memória Espacial , Camundongos , Animais , Dieta , Neurogênese , Hipocampo , MamíferosRESUMO
BACKGROUND: Dyslipidemia increases cardiovascular disease risk, the leading cause of death worldwide. Under time-restricted feeding (TRF), wherein food intake is restricted to a consistent window of <12 hours, weight gain, glucose intolerance, inflammation, dyslipidemia, and hypercholesterolemia are all reduced in mice fed an obesogenic diet. LDLR (low-density lipoprotein receptor) mutations are a major cause of familial hypercholesterolemia and early-onset cardiovascular disease. METHODS: We subjected benchmark preclinical models, mice lacking LDLR-knockout or ApoE knockout to ad libitum feeding of an isocaloric atherogenic diet either ad libitum or 9 hours TRF for up to 13 weeks and assessed disease development, mechanism, and global changes in hepatic gene expression and plasma lipids. In a regression model, a subset of LDLR-knockout mice were ad libitum fed and then subject to TRF. RESULTS: TRF could significantly attenuate weight gain, hypercholesterolemia, and atherosclerosis in mice lacking the LDLR-knockout mice under experimental conditions of both prevention and regression. In LDLR-knockout mice, increased hepatic expression of genes mediating ß-oxidation during fasting is associated with reduced VLDL (very-low-density lipoprotein) secretion and lipid accumulation. Additionally, increased sterol catabolism coupled with fecal loss of cholesterol and bile acids contributes to the atheroprotective effect of TRF. Finally, TRF alone or combined with a cholesterol-free diet can reduce atherosclerosis in LDLR-knockout mice. However, mice lacking ApoE, which is an important protein for hepatic lipoprotein reuptake do not respond to TRF. CONCLUSIONS: In a preclinical animal model, TRF is effective in both the prevention and regression of atherosclerosis in LDLR knockout mice. The results suggest TRF alone or in combination with a low-cholesterol diet can be a lifestyle intervention for reducing cardiovascular disease risk in humans.
Assuntos
Aterosclerose , Modelos Animais de Doenças , Fígado , Camundongos Knockout para ApoE , Receptores de LDL , Animais , Receptores de LDL/genética , Receptores de LDL/deficiência , Aterosclerose/prevenção & controle , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/etiologia , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Fatores de Tempo , Jejum/sangue , Camundongos , Hipercolesterolemia/genética , Hipercolesterolemia/metabolismo , Hipercolesterolemia/complicações , Dieta Aterogênica , Aumento de Peso , Camundongos Knockout , Doenças da Aorta/prevenção & controle , Doenças da Aorta/genética , Doenças da Aorta/patologia , Doenças da Aorta/metabolismo , Lipídeos/sangue , Apolipoproteínas ERESUMO
Ketogenic diets (KDs), fasting, or prolonged physical activity elevate serum ketone bodies (KBs) levels, providing an alternative fuel source for the brain and other organs. However, KBs play pleiotropic roles that go beyond their role in energy production. KBs can act as signaling metabolites, influence gene expression, proteins' posttranslational modifications (PTMs), inflammation, and oxidative stress. Here, we explore the impact of KBs on mammalian cell physiology, including aging and tissue regeneration. We also concentrate on KBs and cancer, given the extensive evidence that dietary approaches inducing ketosis, including fasting-mimicking diets (FMDs) and KDs, can prevent cancer and affect tumor progression.
Assuntos
Corpos Cetônicos , Neoplasias , Animais , Humanos , Corpos Cetônicos/metabolismo , Corpos Cetônicos/farmacologia , Neoplasias/metabolismo , Encéfalo/metabolismo , Estresse Oxidativo , Fenômenos Fisiológicos Celulares , Mamíferos/metabolismoRESUMO
Adipose tissue is the site of long-term energy storage. During the fasting state, exercise, and cold exposure, the white adipose tissue mobilizes energy for peripheral tissues through lipolysis. The mobilization of lipids from white adipose tissue to the liver can lead to excess triglyceride accumulation and fatty liver disease. Although the white adipose tissue is known to release free fatty acids, a comprehensive analysis of lipids mobilized from white adipocytes in vivo has not been completed. In these studies, we provide a comprehensive quantitative analysis of the adipocyte-secreted lipidome and show that there is interorgan crosstalk with liver. Our analysis identifies multiple lipid classes released by adipocytes in response to activation of lipolysis. Time-dependent analysis of the serum lipidome showed that free fatty acids increase within 30 min of ß3-adrenergic receptor activation and subsequently decrease, followed by a rise in serum triglycerides, liver triglycerides, and several ceramide species. The triglyceride composition of liver is enriched for linoleic acid despite higher concentrations of palmitate in the blood. To further validate that these findings were a specific consequence of lipolysis, we generated mice with conditional deletion of adipose tissue triglyceride lipase exclusively in adipocytes. This loss of in vivo adipocyte lipolysis prevented the rise in serum free fatty acids and hepatic triglycerides. Furthermore, conditioned media from adipocytes promotes lipid remodeling in hepatocytes with concomitant changes in genes/pathways mediating lipid utilization. Together, these data highlight critical role of adipocyte lipolysis in interorgan crosstalk between adipocytes and liver.
Assuntos
Ácidos Graxos não Esterificados , Lipólise , Camundongos , Animais , Lipólise/fisiologia , Ácidos Graxos não Esterificados/metabolismo , Lipidômica , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Fígado/metabolismo , Triglicerídeos/metabolismoRESUMO
Type 2 diabetes is a leading cause of global mortality and morbidity. Nearly 80% of individuals with diabetes live in low- and middle-income countries (LMICs), where nearly half of those with the condition remain undiagnosed. The majority of known cases have sub-optimal clinical outcomes. Moreover, large populations with impaired glucose tolerance and/or impaired fasting glucose contribute to the rapid increase in type 2 diabetes. Globally, priority should be given to limit the population with diabetes, especially in LMICs, alongside actions to optimise the care of people diagnosed with diabetes. Primary prevention studies in LMICs have generated evidence to show the efficacy and scalability of strategies to fully prevent or delay the development of diabetes in high-risk groups. However, these are mainly limited to certain countries in Asia, particularly China and India. The studies have indicated that prevention policies are effective in populations with a high risk of type 2 diabetes, and they also have long-term benefits, not only for the risk of type 2 diabetes but also for the risk of associated metabolic disorders, such as CVDs. For the effective conduct of national programmes, innovative mechanisms must be implemented, such as the use of information technology, joint efforts of multiple teams implementing similar programmes, and involvement of governmental and non-governmental partnerships. Continuous monitoring and long-term studies are required to assess the utility of these programmes. The effectiveness of such programmes in LMICs has not been proven over the longer term, except in China. Despite the available evidence, the feasibility of prevention strategies for type 2 diabetes in LMICs at population level remains an enigma. There remain challenges in the form of cultural, societal and economic constraints; insufficient infrastructure and healthcare capacity; and the non-fully elucidated natural history and determinants of type 2 diabetes in LMICs.
Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/prevenção & controle , Países em Desenvolvimento , Estudos de Viabilidade , Atenção à SaúdeRESUMO
AIMS/HYPOTHESIS: Sodium-glucose co-transporter 2 (SGLT2) inhibitors (SGLT2i) are antihyperglycaemic drugs that protect the kidneys of individuals with type 2 diabetes mellitus. However, the underlying mechanisms mediating the renal benefits of SGLT2i are not fully understood. Considering the fuel switches that occur during therapeutic SGLT2 inhibition, we hypothesised that SGLT2i induce fasting-like and aestivation-like metabolic patterns, both of which contribute to the regulation of metabolic reprogramming in diabetic kidney disease (DKD). METHODS: Untargeted and targeted metabolomics assays were performed on plasma samples from participants with type 2 diabetes and kidney disease (n=35, 11 women) receiving canagliflozin (CANA) 100 mg/day at baseline and 12 week follow-up. Next, a systematic snapshot of the effect of CANA on key metabolites and pathways in the kidney was obtained using db/db mice. Moreover, the effects of glycine supplementation in db/db mice and human proximal tubular epithelial cells (human kidney-2 [HK-2]) cells were studied. RESULTS: Treatment of DKD patients with CANA for 12 weeks significantly reduced HbA1c from a median (interquartile range 25-75%) of 49.0 (44.0-57.0) mmol/mol (7.9%, [7.10-9.20%]) to 42.2 (39.7-47.7) mmol/mol (6.8%, [6.40-7.70%]), and reduced urinary albumin/creatinine ratio from 67.8 (45.9-159.0) mg/mmol to 47.0 (26.0-93.6) mg/mmol. The untargeted metabolomics assay showed downregulated glycolysis and upregulated fatty acid oxidation. The targeted metabolomics assay revealed significant upregulation of glycine. The kidneys of db/db mice undergo significant metabolic reprogramming, with changes in sugar, lipid and amino acid metabolism; CANA regulated the metabolic reprogramming in the kidneys of db/db mice. In particular, the pathways for glycine, serine and threonine metabolism, as well as the metabolite of glycine, were significantly upregulated in CANA-treated kidneys. Glycine supplementation ameliorated renal lesions in db/db mice by inhibiting food intake, improving insulin sensitivity and reducing blood glucose levels. Glycine supplementation improved apoptosis of human proximal tubule cells via the AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway. CONCLUSIONS/INTERPRETATION: In conclusion, our study shows that CANA ameliorates DKD by inducing fasting-like and aestivation-like metabolic patterns. Furthermore, DKD was ameliorated by glycine supplementation, and the beneficial effects of glycine were probably due to the activation of the AMPK/mTOR pathway.
Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Inibidores do Transportador 2 de Sódio-Glicose , Camundongos , Animais , Humanos , Feminino , Canagliflozina/farmacologia , Canagliflozina/uso terapêutico , Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/metabolismo , Reprogramação Metabólica , Proteínas Quinases Ativadas por AMP/metabolismo , Transportador 2 de Glucose-Sódio/metabolismo , Estivação , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/metabolismo , Rim/metabolismo , Jejum , Serina-Treonina Quinases TOR/metabolismo , Glicina/metabolismo , Mamíferos/metabolismoRESUMO
AIMS/HYPOTHESIS: The aim of this study was to evaluate the impact on metabolic control of periodic use of a 5-day fasting-mimicking diet (FMD) programme as an adjunct to usual care in people with type 2 diabetes under regular primary care surveillance. METHODS: In this randomised, controlled, assessor-blinded trial, people with type 2 diabetes using metformin as the only glucose-lowering drug and/or diet for glycaemic control were randomised to receive 5-day cycles of an FMD monthly as an adjunct to regular care by their general practitioner or to receive regular care only. The primary outcomes were changes in glucose-lowering medication (as reflected by the medication effect score) and HbA1c levels after 12 months. Moreover, changes in use of glucose-lowering medication and/or HbA1c levels in individual participants were combined to yield a clinically relevant outcome measure ('glycaemic management'), which was categorised as improved, stable or deteriorated after 1 year of follow-up. Several secondary outcome measures were also examined, including changes in body weight. RESULTS: One hundred individuals with type 2 diabetes, age 18-75 years, BMI ≥27 kg/m2, were randomised to the FMD group (n=51) or the control group (n=49). Eight FMD participants and ten control participants were lost to follow-up. Intention-to-treat analyses, using linear mixed models, revealed adjusted estimated treatment effects for the medication effect score (-0.3; 95% CI -0.4, -0.2; p<0.001), HbA1c (-3.2 mmol/mol; 95% CI -6.2, -0.2 and -0.3%; 95% CI -0.6, -0.0; p=0.04) and body weight (-3.6 kg; 95% CI -5.2, -2.1; p<0.001) at 12 months. Glycaemic management improved in 53% of participants using FMD vs 8% of control participants, remained stable in 23% vs 33%, and deteriorated in 23% vs 59% (p<0.001). CONCLUSIONS/INTERPRETATION: Integration of a monthly FMD programme in regular primary care for people with type 2 diabetes who use metformin as the only glucose-lowering drug and/or diet for glycaemic control reduces the need for glucose-lowering medication, improves HbA1c despite the reduction in medication use, and appears to be safe in routine clinical practice. TRIAL REGISTRATION: ClinicalTrials.gov NCT03811587 FUNDING: The project was co-funded by Health~Holland, Top Sector Life Sciences & Health, the Dutch Diabetes Foundation and L-Nutra.
Assuntos
Glicemia , Diabetes Mellitus Tipo 2 , Jejum , Hemoglobinas Glicadas , Controle Glicêmico , Hipoglicemiantes , Metformina , Atenção Primária à Saúde , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/dietoterapia , Pessoa de Meia-Idade , Masculino , Feminino , Jejum/sangue , Metformina/uso terapêutico , Hipoglicemiantes/uso terapêutico , Idoso , Hemoglobinas Glicadas/metabolismo , Glicemia/metabolismo , Glicemia/efeitos dos fármacos , Adulto , Controle Glicêmico/métodos , Resultado do Tratamento , Adolescente , Adulto JovemRESUMO
This study aimed to examine the impact of SCD Probiotics supplementation on liver biomolecule content and histological changes during a 30-day intermittent fasting (IF) program in 24-month-old male Sprague-Dawley rats. Rats underwent 18-h daily fasting and received 1 × 108 CFU of SCD Probiotics daily. Liver tissue biomolecules were analysed using FTIR Spectroscopy, LDA, and SVM techniques, while histopathological evaluations used Haematoxylin and eosin and Masson trichrome-stained tissues. Blood samples were collected for biochemical analysis. Gross alterations in the quantity of biomolecules were observed with individual or combined treatments. LDA and SVM analyses demonstrated a high accuracy in differentiating control and treated groups. The combination treatments led to the most significant reduction in cholesterol ester (1740 cm-1 ) and improved protein phosphorylation (A1239 /A2955 and A1080 /A1545 ) and carbonylation (A1740 /A1545 ). Individually, IF and SCD Probiotics were more effective in enhancing membrane dynamics (Bw2922 /Bw2955 ). In treated groups, histological evaluations showed decreased hepatocyte degeneration, lymphocyticinfiltration, steatosis and fibrosis. Serum ALP, LDH and albumin levels significantly increased in the SCD Probiotics and combined treatment groups. This study offers valuable insights into the potential mechanisms behind the beneficial effects of IF and SCD Probiotics on liver biomolecule content, contributing to the development of personalized nutrition and health strategies.
Assuntos
Hepatopatias , Probióticos , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Jejum Intermitente , Fígado/patologia , Hepatopatias/patologia , FibroseRESUMO
This research aims to investigate the effects of plasma from 12-month-old intermittently fasting rats (IFpls) and untreated rats (Npls) on the liver biomolecules and histological changes in 24-month-old male Sprague-Dawley rats. Fasting rats underwent an 18-h daily fasting period and a 6-h feeding window for 35 days. The plasma was administered bi-daily, and blood samples were examined for specific liver biomolecules. Fourier transform infrared (FTIR) spectroscopy and linear discriminant analysis (LDA) was used to identify molecular profiles. Liver sections were stained for histopathological evaluation, and the expression levels of Notch signalling pathway components were assessed. Distinct molecular profiles were identified across liver biomolecules, lipids, proteins and nucleic acids with high accuracy. Notably, IFpls was found to protect against hepatic instability, microvesicular steatosis and liver fibrosis by decreasing lymphatic infiltration density and Notch pathway expression levels. Both treatments reduced protein oxidation and carbonylation, with Npls showing a pronounced decrease in protein oxidation. Furthermore, Npls increased protein conformation and glycogen/phosphate content, while IFpls increased glucose/protein content. Both IFpls and Npls induce substantial and unique alterations in liver biomolecules. IFpls offers a protective effect on various liver conditions, while Npls exhibits promising results in reducing protein oxidation and altering biomolecule content. These findings offer valuable insights for future research and potential therapeutic approaches.